From: Stanislaw Pal <kuncy7@gmail.com>
To: Bjorn Andersson <andersson@kernel.org>,
	Stephen Boyd <sboyd@kernel.org>,
	Michael Turquette <mturquette@baylibre.com>
Cc: Gabor Juhos <j4g8y7@gmail.com>,
	Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>,
	Jie Luo <jie.luo@oss.qualcomm.com>,
	Georg Seema <georgseema@gmail.com>,
	Mieczyslaw Nalewaj <namiltd@yahoo.com>,
	Brian Masney <bmasney@redhat.com>,
	linux-arm-msm@vger.kernel.org,
	linux-clk@vger.kernel.org,
	linux-kernel@vger.kernel.org,
	stable@vger.kernel.org
Subject: Re: [PATCH v4] clk: qcom: ipq-cmn-pll: keep the CMN block bus clocks enabled
Date: Fri, 25 Sep 2026 16:32:28 +0200
Message-ID: <20260925143228.386299-1-kuncy7@gmail.com>
In-Reply-To: <20260813093351.178419-1-kuncy7@gmail.com>
References: <20260813093351.178419-1-kuncy7@gmail.com>
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Please drop this patch.

Gabor's fix for the same hang has been applied:

  33f9cb56cc28 ("clk: qcom: gcc-ipq5018: mark 'gpll0_main' clock as critical")

It addresses the platform-level cause: 'gpll0_main' feeds the CPUs
through GPLL0 during early boot, before the APCS clock is registered
and CCF can see that consumer, so the first driver to drop a runtime PM
reference on a GCC clock under it takes the CPUs down with it. The
ipq-cmn-pll probe was only the first driver to do so on the AX55 v1; I
had verified on that board that Gabor's change alone gives a reliable
boot with this patch absent, and OpenWrt has since replaced this patch
with his in its tree.

That also answers the two open questions here. Jie's suggestion of
making the GCC a consumer of the CMN PLL outputs is no longer needed
for this hang, and Konrad's question about crashdump mode I cannot
answer: I never captured that state, and with the fix in place I have
nothing left that reproduces it.

Thank you all for the review, and Gabor for finding the actual cause.

Best regards,
Stanislaw